The Experts below are selected from a list of 132 Experts worldwide ranked by ideXlab platform

B. Babál - One of the best experts on this subject based on the ideXlab platform.

  • Long-term behaviour of plain and steel fibre reinforced concrete rings
    Materials and Structures, 1992
    Co-Authors: T. Nürnbergerová, B. Babál
    Abstract:

    The effects of long-term loading on plain (PLC) and steel fibre reinforced concrete (SFRC) rings under two-edge sustained load at five different levels were investigated. The results have led to the conclusion that a Linear relationship between the initial and time-dependent deformations can be supposed. The intercept term of the Regression Straight Line was found to be equal to the deformation caused by pure shrinkage. In spite of cracks appearing at higher loading levels the Linearity was not distorted. The results indicate that an exponential function including one retardation time can be applied in practical computation of long-term deformations.

  • Long-term behaviour of plain and steel fibre reinforced concrete rings
    Materials and Structures, 1992
    Co-Authors: T. Nürnbergerová, B. Babál
    Abstract:

    On a étudie le comportement d’anneaux de béton non armé (PLC) et de béton renforcé de fibres d’acier (SFRC) chargés au bord dans deux directions différentes sous cinq charges différentes. Les résultats laissent supposer qu’il peut exister une relation entre les déformations initiales et celles qui se développent avec le temps. On a trouvé que l’intercept de la ligne droite de régression était égal à la déformation déterminée par le seul retrait. En dépit des fissures qui apparaissent à des niveaux de charges plus élevés, on n’a pas observé de distortion de la linéarité. Les résultats montrent qu’on peut appliquer une fonction exponentielle comprenant un temps de retard au calcul pratique des déformations à long terme. The effects of long-term loading on plain (PLC) and steel fibre reinforced concrete (SFRC) rings under two-edge sustained load at five different levels were investigated. The results have led to the conclusion that a Linear relationship between the initial and time-dependent deformations can be supposed. The intercept term of the Regression Straight Line was found to be equal to the deformation caused by pure shrinkage. In spite of cracks appearing at higher loading levels the Linearity was not distorted. The results indicate that an exponential function including one retardation time can be applied in practical computation of long-term deformations.

Michele Pisante - One of the best experts on this subject based on the ideXlab platform.

  • no tillage and conventional tillage effects on durum wheat yield grain quality and soil moisture content in southern italy
    Soil & Tillage Research, 2007
    Co-Authors: Pasquale De Vita, Emmanuel Di Paolo, G Fecondo, Natale Di Fonzo, Michele Pisante
    Abstract:

    Abstract No-tillage (NT) is becoming increasingly attractive to farmers because it clearly reduces production costs relative to conventional tillage (CT). However, many producers in southern Italy are reluctant to adopt this practice because NT can have contrasting consequences on grain yield depending on weather conditions. The effect of NT and CT on continuous durum wheat ( Triticum durum Desf.) under rainfed Mediterranean conditions was studied, over a 3-year period (2000–2002) at two locations (Foggia and Vasto) in southern Italy. Yield, grain quality [thousand kernel weight (TKW), test weight (TW) and protein content (PC)] and soil water content were assessed. Higher yield was obtained with NT than CT in the first 2 years at Foggia. In contrast, mean yield and quality parameters at Vasto were similar for the two treatments, except in the third year in which CT produced more than NT (4.6 Mg ha −1 versus 2.9 Mg ha −1 ). At Foggia, TW and TKW were higher in NT than CT in all years. Highest PC was obtained under CT (19.6% and 15.5% for CT versus 14.7% and 11.4% for NT, respectively, in the growing season 2000–2001 and 2001–2002) indicating that grain was shriveled with low starch accumulation. At Foggia, where this study was part of a long-term experiment started in 1995, a strong correlation was observed between yield and rainfall during the wheat growing season. The coefficient of determination ( R 2 ) values for CT and NT were 0.69 * and 0.31 ns, respectively, and the Regression Straight Line crossed around 300 mm of rainfall. These results indicate that NT was superior below this rainfall value, whereas more rainfall enhanced yield in CT. We conclude that NT performed better at Foggia with limited rainfall during the durum wheat growing season. The superior effect of NT in comparison to CT, was due to lower water evaporation from soil combined with enhanced soil water availability.

M.b. Ćelap - One of the best experts on this subject based on the ideXlab platform.

  • Linear interdependence ofRM pair values of substances in salting-out planar chromatography
    Chromatographia, 1996
    Co-Authors: Tomislav J. Janjić, Gordana Vučković, M.b. Ćelap
    Abstract:

    It has been established that in salting-out planar chromatography there is a Linear dependence between the pair ofRM values of substances obtained on one or two sorbents using the same series of aqueous ammonium sulphate solutions (RM pair Linearity rule). In addition, the proportionality between the distance of the individual points on the Regression Straight Line and the difference in mol% of the salt in the corresponding solvents has been established (proportionality rule).

  • Linear interdependence ofR _M pair values of substances in salting-out planar chromatography
    Chromatographia, 1996
    Co-Authors: Tomislav J. Janjić, Gordana Vučković, M.b. Ćelap
    Abstract:

    It has been established that in salting-out planar chromatography there is a Linear dependence between the pair of R _M values of substances obtained on one or two sorbents using the same series of aqueous ammonium sulphate solutions ( R _M pair Linearity rule). In addition, the proportionality between the distance of the individual points on the Regression Straight Line and the difference in mol% of the salt in the corresponding solvents has been established (proportionality rule).

T. Nürnbergerová - One of the best experts on this subject based on the ideXlab platform.

  • Long-term behaviour of plain and steel fibre reinforced concrete rings
    Materials and Structures, 1992
    Co-Authors: T. Nürnbergerová, B. Babál
    Abstract:

    The effects of long-term loading on plain (PLC) and steel fibre reinforced concrete (SFRC) rings under two-edge sustained load at five different levels were investigated. The results have led to the conclusion that a Linear relationship between the initial and time-dependent deformations can be supposed. The intercept term of the Regression Straight Line was found to be equal to the deformation caused by pure shrinkage. In spite of cracks appearing at higher loading levels the Linearity was not distorted. The results indicate that an exponential function including one retardation time can be applied in practical computation of long-term deformations.

  • Long-term behaviour of plain and steel fibre reinforced concrete rings
    Materials and Structures, 1992
    Co-Authors: T. Nürnbergerová, B. Babál
    Abstract:

    On a étudie le comportement d’anneaux de béton non armé (PLC) et de béton renforcé de fibres d’acier (SFRC) chargés au bord dans deux directions différentes sous cinq charges différentes. Les résultats laissent supposer qu’il peut exister une relation entre les déformations initiales et celles qui se développent avec le temps. On a trouvé que l’intercept de la ligne droite de régression était égal à la déformation déterminée par le seul retrait. En dépit des fissures qui apparaissent à des niveaux de charges plus élevés, on n’a pas observé de distortion de la linéarité. Les résultats montrent qu’on peut appliquer une fonction exponentielle comprenant un temps de retard au calcul pratique des déformations à long terme. The effects of long-term loading on plain (PLC) and steel fibre reinforced concrete (SFRC) rings under two-edge sustained load at five different levels were investigated. The results have led to the conclusion that a Linear relationship between the initial and time-dependent deformations can be supposed. The intercept term of the Regression Straight Line was found to be equal to the deformation caused by pure shrinkage. In spite of cracks appearing at higher loading levels the Linearity was not distorted. The results indicate that an exponential function including one retardation time can be applied in practical computation of long-term deformations.

K.f. Hubner - One of the best experts on this subject based on the ideXlab platform.

  • Linear least squares compartmental-model-independent parameter identification in PET
    IEEE Transactions on Medical Imaging, 1997
    Co-Authors: J.a. Thie, G.t. Smith, K.f. Hubner
    Abstract:

    A simplified approach involving Linear-Regression Straight-Line parameter fitting of dynamic scan data is developed for both specific and nonspecific models. Where compartmental-model topologies apply, the measured activity may be expressed in terms of: its integrals, plasma activity and plasma integrals-all in a Linear expression with macroparameters as coefficients. Multiple Linear Regression, as in spreadsheet software, determines parameters for best data fits. Positron emission tomography (PET)-acquired gray-matter images in a dynamic scan are analyzed: both by this method and by traditional iterative nonLinear least squares. Both patient and simulated data were used. Regression and traditional methods are in expected agreement. Monte-Carlo simulations evaluate parameter standard deviations, due to data noise, and much smaller noise-induced biases. Unique Straight-Line graphical displays permit visualizing data influences on various macroparameters as changes in slopes. Advantages of Regression fitting are: simplicity, speed, ease of implementation in spreadsheet software, avoiding risks of convergence failures or false solutions in iterative Least squares, and providing various visualizations of the uptake process by Straight Line graphical displays. Multiparameter model-independent analyses on lesser understood systems is also made possible.